Lock-seam pipe.



PATENTED FEB. 13, 1906.

H. P. G. NORSTRAND.

LOCK SBAM PIPE.

APPLICATION FILED JAN.24,1903.

JUUQYZEFE 6W aw 1 @J vca' W UNITED STATES PATENT OFFICE.

HANS P. G. NORSIFRANI), OF CHICAGO. ILLINOIS.

LOCK-SEAM PIPE.

Specification of Letters Patent.

Patented Feb. 13, 1906.

Application filed January 24:, 1903. Serial No. 140,432.

[ all whom it may concern.-

Be it known that I, HANs P. G. N ORSTRANI),

residing at Chicago, 'Cook county, Illinois,

of the adjacent edges of the pipe and the sealing thereof so as to be fluid-tight.

The novel and advantageous features of construction and operation will be understood from the description hereinafter given.

In the drawings, Figure 1 is a section of a completed pipe embodying my invention,

and Figs. 2, 3, and 4 detail views illustrating different steps in the formation of the parts.

A proper understanding of my invention can best be arrived at by following the different steps of the process of formation of the pipe and my novel joint or seam therein, beginning with the plate or sheet and ending with the completed article or pipe. In this connection it may be said that the plate or sheet may be of suitable or desired material and thickness and the resulting pipe of the desired diameter.

Referring first to Figs. 2, 3, and 4, the plate or sheet 1, which is to form the body of the pipe, is rolled over as to two opposite edges, so as to provide thickened portions 2, which are formed by bending the edges of the plate over upon wires 3, as seen in Fig. '2, preferably with the longitudinal axis of the plate passing through the center'of the wires to obtain advantages hereinafter explained. After the edges of the plate are turned or bent over, as described, the next step is to roll the plate to a circle, as illustrated in Fig. 3, wherein the edges are shown in proximity, after which the locking-strip 4 is inserted in place, as shown in Fig. 4. In the present instance this locking-strip, which may be of steel, wrought-iron, or other suitable material, is of I-beam section, with the web. portion arranged between the edges of the pipe and the top and bottom flanges 6 and 7 thereof respectively located 'exteriorly and interiorly of the pipe. At the proper time, preferably before the locking-strip is inserted in place, suitable packing 5, eitherfibrous or metallic, is arranged or laid along the web of the locking-strip so as to belocated in the finished pipe between such web and the edges of the pipe, as Well as against the top and bottom flanges of the strip. The next step is the pressing together of the parts of the joint by suitable pressing appliances or machinery, such as a hydraulic press, whereby such parts assume the relative posit-ion and condition illustrated in Fig. 1. The resiliency or clasticity ofthe metal of which the pipe is formed gives the loop bent around the wire 2 a tendency to spring out after it is formed, and this tendency, by permitting the loop to yield when the locking-strip is bent over the edges and causing it to spring out again when the pressure is removed, thus maintaining close contact with the inside surfaces of the locking strip, makes it possible to secure a tight joint. In the completed pipe the lockingstrip is bent over upon the enlarged edges of the pipe and substantially incloses them, as shown in' Fig. 1, whereby a rigid seam or joint is obtained. Moreover, the packing into which the parts are compressed effectually seals the joint.

As hereinbefore stated, the longitudinal axis of the plate by preference passes through vantage of this arrangement is that strain on the shell due to internal pressure will be carried uniformly by the inside and outside flanges of the locking-strip, inasmuch as the strain or pull of each half of the enlarged edges will be taken by its respective flange of the. locking-strip.

By this arrangement av shoulder is reduced at the base of the loop or turn w ich forms the enlarged edge or terminal portion, and this, cooperating with the shoulder formed by the bending over of the correspond ing flange of the locking-strip, causes any strain tending to open the seam to fall more directly on the sheet metal, and thus prevents the uncoiling of the turned-over p'ortion.

- I claim 1. A lock-seam pipe, comprising the pipe roper formed of sheet metal and having a ongitudina'l seam, wires extending longitudi nally of the pipe and over which the longitudinal edges of the pipe are turned to form enlarged terminal portions having a shoulder at the base of the turn, and a locking strip arranged to be bent over and clamped around said enlarged terminal portions, said lockingstri having a shoulder adapted to cooperate wit the shoulder on the enlarged terminal portion.

3o 5. A-lock-seam pipe having a longitudinal or seam.

2. A lock seani pi )e comprising the shell longitudinal seam, the longitudinal edges of or pipe proper tonne of sheet metal and havthe pipe adjacent to the seam being turned ing a longitudinal seam, wires over which the l back upon themselves in an open loop to form 6 5 longitudinal edges of the pipe are turned, and l elastic enlargements, and a locking-strip of 5 whose longitudinal axis lies on the neutral. substantially I-beam section Whose web poraxis of the shell, and a'looking-stri engaging and holding such edges to lock t e joint-or seam.

3. A lock-seam pipe having a longitudinal 1o seam and comprising the shell or pipe-body whose longitudinal edges are flat and of-a thickness uniform with the shell, wires over which such ed es are, turned and Whose lonitudinal axis pipe, and whose top and bottom anges are pressed upon and substantially surround said elastic enlargements. j

9. A lock-seam pipe, comprising the pipe roper formed of sheet metal and having a ongitudinal seam, Wires over which the longitudinal edges of the pipe are turned to-form 7 5 asubstantially cylindrical enlargement Whose longitudinal axis lies in the neutral axis of the shell of the pipe, and a locking-strip of substantially Ibeam section arranged to engage and hold said edges, i

10. Alock-seam ipe, com rising thepipe proper formed of s eet meta and having a on itudinal seam, the longitudinal edgesof sai pipe being turned back on themselves in i an open loop to form elastic enlargements of rounded exterior, a locking-strip of substantially I-beam section arranged to engage and hold such enlarged edges, and packing interposed in the space lying between the rounded exterior of said enlargements and the angular 9o interior surfaces of'said I-beam locking-strip.

' 11. A lock-seam pipe, comprising the pipe proper formed of sheet metal and having a longitudinal seam, wires extending along the edges of the pipe adjacent to said seam and over which the edges of the pipe are turned, without being rigidly secured thereto to form a shoulder at the base of the turn, and a locking-strip arranged to engage and hold said edges, said. strip having a ortion adapted to cooperate With said 'shoul er.

12. A lock-seam pipe, comprisingthe shell proper having a longitudinal seam, wiresextending along said seam over which the longitudinal edges oflthe pipe. are turned, but not rigidly securedthereto, the longitudinal axes of said wires lying in the neutral axis of said pipe, and a locking-strip clamped upon said edges to lock the'j oint or seam.

ies on the neutral axis of the 15 shell, and a locking-stri engaging and holding such edges to lock t e joint or seam.

4. A lock-seam pipe having a longitudinal seam and-comprising'the shell or pi e-body formed of sheet metal, Wires over w 'ch the 20 longitudinal edges of the pipe are turned to form a shoulder at the base of the turn, and a locking device consistingof an I-shaped'strip whoseflange portions arebent over the edges of the pipe with their extreme ends abutting 2 5 the body of the pipe, one of said flange portions forming a shoulder adapted to cooperate with the shoulder at the base of the turn, whereby such flange portions embrace such edges and lock the joint or seam.

seam, and comprising the shell-or pipe-body formed of sheet metal, wires over which the longitudinal edges of the pipe are turnedto form enlarged terminal portions having a 3 5 shoulder extending along the base of the turn, and a locking device consisting of an I-shaped strip whose flange portions are bent over the enlarged terminal portions of the pipe, one of said flange portions forming a shoulder adapt 40 ed to cooperate with the shoulder at the base of the turn, and packing arranged in the inner corners of the locking-strip to seal the joint or seam,

6. A lock-seam. pipe, comprising the pipe 45 proper formed of sheet metal and having'a ongitudinal seam, the edges of said pipe be- 7 ing turned back upon themselves in an open loop to form enlargerv and elastic terminal 13. Alock-seam pipe,-com'pr1sing the pipeportions, and a locking-strip engaging and body formed-of sheet metal and having a lon- 50 holding such enlarged and elastic terminals gitudinal seam the edges of said pipe-body to lock the joint or seam. being turned back upon themselves in an 7. A lock-seam. pipe, comprising the" pipe open loop the base of whichprojects outside roper formed of sheet metal and having a of the plane of the pipe to form a shoulder, ongitudinal seam, Wires over whichthe lonsaid loop forming an enlarged terminal por- 55 gitudinal edges of the pipe are turned, withtion, and a locking-strip adapted to embrace out being'brought into close contact there- 1 the said terminalportions and having ashoulwith, to form enlarged and elastic terminal der adapted to cooperate with the'shoulder at portions, and a locking-strip arranged to enthe base of the turn. gage and hold said portionsto lock the, joint HANS P. G. NORSTRAND, Witnesses: 1 8. A lock-seam pipe, comprising the pipe S. E. HIBBEN, proper formed of sheetmetal and-having a 1 LOUIS B. ERWIN.

tion is arranged between the ed es of the I 

